CN106056587B - Full view line laser structured light three-dimensional imaging caliberating device and method - Google Patents

Abstract

The invention discloses a laser scanning three-dimensional imaging calibration device and method for a full viewing angle. The full-view laser scanning three-dimensional imaging calibration device of the present invention includes a one-dimensional moving part, a calibration block, a laser emitter and a camera. The calibration block is installed on the one-dimensional moving part, and the calibration block is a polyhedron with at least three faces. Several faces of the block surround each other in the circumferential direction, and each face of the calibration block is fixed with a calibration plate, and several calibration plates surround each other in the circumferential direction; the number of laser emitters and cameras corresponds to the number of calibration plates, and several laser emitters are aligned along the ring. The direction is arranged facing the calibration block; each camera is equipped with a lens, and the lens images the calibration plate. The full-view laser scanning three-dimensional imaging calibration device of the present invention has a simple structure, is convenient for operation and processing, is applicable to calibration of various sizes of fields of view, and makes up for the shortcoming of incomplete imaging of a single system.

Description

Laser scanning three-dimensional imaging calibration device and method for full viewing angle

technical field

The invention belongs to the technical field of three-dimensional laser measurement, and in particular relates to a full-view laser scanning three-dimensional imaging calibration device and method.

Background technique

The method of line laser triangulation scanning three-dimensional imaging is a non-contact optical active three-dimensional measurement method, which uses the mathematical principle of trigonometry to obtain the three-dimensional coordinates of the measurement point by calculating and analyzing the optical image with depth information, and outputs it through data processing desired measurement results. Specifically, using a laser as an active light source, the line laser emitted by the laser is projected onto the surface of the object to be scanned, and its reflected image is imaged on the industrial camera through the imaging objective lens. Displacement, and the position of the image point has a unique geometric correspondence with the height information of the object surface at the projection point. Through the measurement and calculation of a series of sampled laser lines, the displacement information of the object or the depth change of the surface profile can be obtained.

However, the existing line laser scanning 3D imaging device only performs 3D scanning for one angle of the object to be scanned, and at the same time, it is used for the morphological changes of the surface of the object to be scanned to cause certain data loss on the measured surface, the application range is relatively small, and cannot Get comprehensive information on the object to be scanned.

Contents of the invention

In order to solve the above-mentioned problems in the prior art, the present invention discloses a full-view laser scanning three-dimensional imaging calibration device and method.

The present invention studies a new calibration method, builds an experimental device, and enables multiple cameras to collect multi-angle surface data of the object to be scanned at the same time, calculates the three-dimensional data of the surface profile, and uses the new calibration technology to separate the data obtained by multiple cameras. The point cloud data is matched and overlapped to increase the three-dimensional data scanning information points of the measured surface, so as to realize the full-angle and all-round scanning of the object to be scanned.

The invention can not only adapt to the surface contour characteristics of small objects, but also measure the appearance of large-sized objects. The measurement system has simple structure, convenient maintenance, high flexibility, and high measurement accuracy, and can be applied to various working scenes and demand.

In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions: a full-view laser scanning three-dimensional imaging calibration device, including a one-dimensional moving part, a calibration block, a laser emitter and a camera, and the calibration block is installed on the one-dimensional moving Components, the calibration block is a polyhedron with at least three faces, several faces of the calibration block surround each other in the circumferential direction, a calibration plate is respectively fixed on each face of the calibration block, and several calibration plates surround each other in the circumferential direction; the laser transmitter and The number of cameras corresponds to the number of calibration plates, and several laser emitters are arranged in a circular direction facing the calibration blocks; each camera is equipped with a lens, and the lens images the calibration plate.

Preferably, the calibration block is a cube, and there are four calibration plates, and the four calibration plates are arranged along the four successively adjacent faces of the calibration block; indivual.

Preferably, the calibration block is a Mitsubishi column, and there are three calibration plates, and the three calibration plates are arranged along three successively adjacent faces of the calibration block; correspondingly, three laser emitters, cameras and lenses are respectively provided .

Preferably, the calibration plate is a standard dot calibration plate.

The laser scanning three-dimensional imaging calibration method of the present invention is carried out according to the following steps:

Step 1-1, building a full-view laser scanning three-dimensional imaging calibration device as described in any one of claims 1-4;

Step 1-2, keep the position of the calibration block (8) unchanged, so that several cameras (2-1, 2-2, 2-3, 2-4) simultaneously collect a corresponding calibration board (7-1, 7 ‐2, 7‐3, 7‐4) images, calculate the coordinates and attitude data of each camera (2‐1, 2‐2, 2‐3, 2‐4), and the calibration board (7‐1, 7‐2, The coordinate system corresponding to 7‐3, 7‐4) is used as the standard world coordinate system of the corresponding camera (2‐1, 2‐2, 2‐3, 2‐4);

Step 1-3, move the calibration block (8), so that each camera (2-1, 2-2, 2-3, 2-4) collects the corresponding calibration board (7-1, 7-2, 7 ‐3, 7‐4) sitting posture and posture data, according to the calibration data of each position, get each camera (2‐1, 2‐2, 2‐3, 2‐4) in the world coordinate system through a predetermined method under the position;

Step 1-4, the one-dimensional moving part (4) drives the calibration block (8) to move, take two images respectively in the direction of motion, and identify each calibration board (7-1, 7-2, 7- 3.7-4) at the same position, obtain the moving direction and distance of the one-dimensional moving device (4);

Step 1‐5, turn on each laser transmitter (1‐1, 1‐2, 1‐3, 1‐4), and use cameras (2‐1, 2‐2, 2‐3, 2‐4) to collect laser emission The image formed by several non-overlapping straight lines in the light plane of the camera (1‐1, 1‐2, 1‐3, 1‐4), find the line laser plane equation, and determine the line laser light plane relative to the camera (2‐1 , 2‐2, 2‐3, 2‐4) the positional relationship between the coordinate system and the world coordinate system;

Step 1-6, remove the calibration block, install the object 5 to be measured on the same position of the one-dimensional moving part 4; adjust the position of the object to be scanned (5) so that the laser line is projected on the object to be scanned (5), use a The three-dimensional moving part (4) drives the object to be scanned (5) to move perpendicular to the plane formed by each laser emitter (1‐1, 1‐2, 1‐3, 1‐4), using the camera (2‐1, 2 ‐2, 2‐3, 2‐4) Simultaneously collect images of the object to be scanned (5), transmit the collected images back to the computer, process the images, and obtain the coordinate data of different surfaces of the scanned object (5);

In step 1-7, the coordinate data of the image obtained by line laser scanning three-dimensional imaging is the standard coordinate system under the calibration board (7-1, 7-2, 7-3, 7-4), while multiple calibration boards (7-2 ‐1, 7‐2, 7‐3, 7‐4) relative positions are known, through the mutual relationship between the standard coordinate systems corresponding to the calibration board (7‐1, 7‐2, 7‐3, 7‐4) Transformation allows multiple cameras (2‐1, 2‐2, 2‐3, 2‐4) to splice images of different surfaces together to complete full-view laser scanning 3D imaging.

Preferably, there are four calibration plates.

Preferably, in step 1-2, set the calibration plate (7-1) on one of the surfaces as the standard world coordinate system (X _W1 , Y _W1 , Z _W1 ), and the calibration plate (7-1) on one of the adjacent surfaces ‐2) is the temporary coordinate system (X _w2 , Y _w2 , Z _w2 ), and so on, the coordinate system of the third calibration plate (7‐3) is the temporary coordinate system (X _w3 , Y _w3 , Z _w3 ), the coordinate system of the fourth calibration plate (7‐4) is the temporary coordinate system (X _w4 , Y _w4 , Z _w4 ).

Preferably, in step 1-7, the images of different surfaces formed by multiple cameras are stitched together, and the specific steps are as follows:

When the one-dimensional motion device (4) drives the object to be scanned (5) to move, the cameras (2‐1, 2‐2, 2‐3, 2‐4) collect a picture every time the object to be scanned (5) moves a certain distance The image of the laser line on the surface of the object to be scanned (5), calculating the height information and splicing the collected multiple laser lines according to the moving direction and distance, to obtain the three-dimensional data on the surface of the object to be scanned (5);

Four sets of three-dimensional data are obtained through four cameras (2‐1, 2‐2, 2‐3, 2‐4), and their coordinates are determined according to the standard coordinate system and temporary coordinate system in step 1‐2; assuming that two of the surfaces The point coordinates in its corresponding standard world coordinate system are (X _Ai , Y _Ai , Z _Ai ), and the point coordinates in the temporary world coordinate system are (X _Bi , Y _Bi , Z _Bi );

The coordinates of the image obtained by line laser scanning three-dimensional imaging are in the world coordinate system, and the relative positions of the two calibration plates (7‐1, 7‐2, 7‐3, 7‐4) are known, that is, through the two world coordinates The mutual transformation between the two cameras (2-1, 2-2, 2-3, 2-4) overlaps the images of different surfaces of the object to be scanned (5);

Because the conversion relationship of the world coordinate system corresponding to these calibration boards is fixed, the conversion relationship between the world coordinate systems corresponding to each calibration board is represented by an orthogonal rotation matrix R and a translation vector T; one of the calibration boards (7-1) is the standard world coordinate system (X _W1 , Y _W1 , Z _W1 ), and the adjacent calibration plate (7‐2) coordinate system is the temporary coordinate system (X _w2 , Y _w2 , Z _w2 ), then the two coordinates The transformation relationship between them is expressed as follows:

Among them, R is a 3×3 orthogonal rotation matrix; T is a three-dimensional translation vector, 0=(0,0,0); M is a 4×4 external parameter matrix, which represents the difference between the standard world coordinate system and the temporary world coordinate system. Transformation relationship between;

Among the two calibration plates, we get Take the side length of the cube as d, then Set the point coordinates in the temporary world coordinate system as Converted to a point in the standard world coordinate system, the formula is

If the two coordinates are displayed in the same coordinate system, two different surfaces of the object to be scanned (5) can be spliced together.

Preferably, in step 1-4, when the one-dimensional moving part (4) drives the calibration block (8) to move, the cameras (2-1, 2-2, 2-3, 2-4) correspondingly collect An image of a calibration board (7‐1, 7‐2, 7‐3, 7‐4), identify and analyze the calibration board (7‐1, 7‐2, 7‐3, 7‐4), and obtain The moving distance of the object (5) is scanned each time, so that three-dimensional data on the surface of the object (5) to be scanned can be obtained by moving images of multiple sets of laser lines at the same moving distance.

The full-view laser scanning three-dimensional imaging calibration device and method of the present invention comprise a calibration block by fixing multiple calibration plates on the surface of a polyhedron with known geometric dimensions, and use the calibration block to calibrate multiple cameras at the same time, and the cameras are collected separately to be Scan the three-dimensional information of different surfaces of the object, and then splicing the information of different surfaces of the object to be measured according to the coordinate transformation to obtain the complete information of the object surface, thereby solving the shortcoming that a single line laser scanning device cannot obtain complete information on the object surface.

The method of the present invention for three-dimensional imaging by full-view laser scanning includes two steps: one is to calibrate the camera through a calibration block, and the other is to scan and image the object to be scanned and splice and combine information from different surfaces.

The full-view laser scanning three-dimensional imaging calibration device of the present invention has a simple structure, is convenient for operation and processing, is applicable to calibration of various sizes of fields of view, and makes up for the shortcoming of incomplete imaging of a single system.

Description of drawings

Fig. 1 is a schematic flow diagram of a scanning three-dimensional imaging calibration method and scanning imaging of a preferred embodiment of full view line laser triangulation.

FIG. 2 is a schematic structural diagram of a preferred embodiment of a full-view line laser triangulation scanning three-dimensional imaging device in the state of scanning an object to be measured.

Fig. 3 is a schematic structural diagram of a preferred embodiment of a laser triangulation scanning three-dimensional imaging calibration device in use.

Fig. 4 is a structural schematic diagram of a preferred calibration board (7-1, 7-2, 7-3, 7-4).

Fig. 5 shows that the calibration plates (7-1, 7-2, 7-3, 7-4) are fixed on four different planes of a cube to form a calibration block (8).

FIG. 6 is a schematic diagram of positions of the standard world coordinate system and the temporary world coordinate system.

Detailed ways

The preferred embodiments of the present invention will be described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

As shown in Figure 2, the full-view laser scanning three-dimensional imaging calibration device in this embodiment includes: four laser emitters (1-1, 1-2, 1-3, 1-4), four industrial cameras (2- 1, 2‐2, 2‐3, 2‐4), four lenses (3‐1, 3‐2, 3‐3, 3‐4), one-dimensional moving parts (4), installed on each industrial camera A lens, mounted sideways, images the calibration plate. An object to be scanned 5 is installed on the one-dimensional moving part 4 .

Four laser emitters are arranged in a ring around the object to be scanned (5), and the four laser emitters 1-1, 1-2, 1-3, 1-4 form a circular surface, and the one-dimensional motion device (4 ) can drive the object to be scanned (5) to move perpendicularly to the plane formed by the lasers (1‐1, 1‐2, 1‐3, 1‐4).

Four industrial cameras each with a lens are aimed at the object 5 to be scanned. After each laser emitter projects laser light to the object 5 to be scanned, the image is collected by one of the industrial cameras and lenses, so that one laser, one An industrial camera and a lens constitute a single line laser scanning 3D imaging assembly.

In this embodiment, the full-view laser scanning three-dimensional imaging calibration device includes four calibration plates (7-1, 7-2, 7-3, 7-4), and the calibration plates are standard dot calibration plates, as shown in Figure 4 , it has the following characteristics:

1). Use the center of each dot on the calibration board as the calibration feature point, and stipulate that the origin of the world coordinate system is located at the center of the circle in the middle. As shown in Figure 6, the Z axis is perpendicular to the plane of the calibration board.

2). The black direction mark on the upper left corner of the calibration board determines the direction of the coordinate system of the calibration board.

Four calibration plates (7-1, 7-2, 7-3, 7-4) are fixed on four successively adjacent faces of a cube block (the four adjacent faces are surrounded by the circumferential direction), so that A calibration block (8) is formed.

When the camera is calibrated by the calibration block, referring to FIG. 3 , the calibration block 8 is installed at the position of the object 5 to be scanned in FIG. 2 .

After the calibration is completed, the calibration block 8 is removed, and the object 5 to be scanned is installed on the same position. The one-dimensional motion device (4) drives the object to be scanned (5) to move perpendicular to the plane surrounded by the four lasers (1‐1, 1‐2, 1‐3, 1‐4), using the industrial camera (2‐1 , 2‐2, 2‐3, 2‐4) and lenses (3‐1, 3‐2, 3‐3, 3‐4) to image it.

The present embodiment is described with the combination of four as an example, for example, the combination of three, five or more also falls within the protection scope of the present invention, wherein, the cube similar to making the calibration block (8) also Other polyhedra of known geometrical dimensions may be used.

In order to realize the three-dimensional imaging of full-view line laser scanning, calibration is a key step. The calibration block (8) plays an important role in the coordinate conversion in the later stage.

FIG. 1 is a schematic flow chart of the scanning three-dimensional imaging calibration method and scanning imaging provided by this embodiment. Referring to Fig. 1, the laser scanning three-dimensional imaging calibration method of the present embodiment includes the following steps:

Step 1-1, set up the experimental device, and use four single-line laser scanning 3D imaging combinations to align the four calibration plates on the calibration block. details as follows:

Using the aforementioned structural design, that is, a laser, an industrial camera and a lens form a single-line laser scanning three-dimensional imaging assembly, and four single-line laser scanning three-dimensional imaging assemblies (along the circumferential direction) are arranged in a ring on the object to be scanned ( 5) around, each assembly corresponds to a calibration plate (7‐1, 7‐2, 7‐3, 7‐4) on the calibration block (8).

A calibration block 8 is installed on the one-dimensional movement device (4), which can drive the calibration block 8 to move, and its motion direction is parallel to or perpendicular to the plane of multiple calibration plates (7‐1, 7‐2, 7‐3, 7‐4). In the plane surrounded by four lasers (1‐1, 1‐2, 1‐3, 1‐4).

Wherein, the calibration plate is generally a standard dot calibration plate, as shown in FIG. 4 . This calibration board has the following characteristics:

1). Use the center of each dot on the calibration board as the calibration feature point, and stipulate that the origin of the world coordinate system is located at the center of the circle in the middle. As shown in Figure 6, the Z axis is perpendicular to the plane of the calibration board.

2). The black direction mark on the upper left corner of the calibration board determines the direction of the coordinate system of the calibration board.

Step 1-2, keep the position of the calibration block unchanged, make the four cameras capture an image of the corresponding calibration board at the same time, and calculate the camera coordinates and attitude data. details as follows:

Keep the position of the calibration block (8) unchanged, so that four cameras (2‐1, 2‐2, 2‐3, 2‐4) simultaneously capture a corresponding calibration board (7‐1, 7‐2, 7‐ 3. 7‐4) image, calculate camera (2‐1, 2‐2, 2‐3, 2‐4) coordinates and attitude data, calibration board (7‐1, 7‐2, 7‐3, 7‐ 4) The corresponding coordinate system is used as the standard world coordinate system of the corresponding camera (2‐1, 2‐2, 2‐3, 2‐4). When collecting, it must be ensured that the position of the calibration block (8) remains unchanged, and at the same time the image of the calibration board (7-1, 7-2, 7-3, 7-4) on the other side cannot be collected.

Fix the calibration plate (7‐1) on one surface as the standard world coordinate system (X _W1 , Y _W1 , Z _W1 ), and the coordinate system of the calibration plate (7‐2) on the adjacent surface is the temporary coordinate system system (X _w2 , Y _w2 , Z _w2 ), the coordinate system of the calibration plate (7‐3) is the temporary coordinate system (X _w3 , Y _w3 , Z _w3 ), and the calibration plate (7‐3) on an adjacent surface ‐4) The coordinate system is the temporary coordinate system (X _w4 , Y _w4 , Z _w4 ), as shown in Figures 5 and 6.

Step 1-3, manually move the calibration block, so that the calibration block is placed in different positions in the camera's field of view, and each time the calibration block is moved, the camera collects the sitting posture and posture data of the corresponding calibration board multiple times to reduce the error. Repeat steps 1-3 many times, generally about 20 times of collection is the best, as follows:

Manually move the calibration block (8), so that the calibration block is placed in different positions in the camera's field of view, and each time the calibration block is moved, the camera (2‐1, 2‐2, 2‐3, 2‐4) collects multiple times The sitting posture and posture data of the corresponding calibration board (7-1, 7-2, 7-3, 7-4), according to the calibration data of each position, get each camera (2-1, 2 ‐2, 2‐3, 2‐4) The position in the world coordinate system, the purpose of multiple acquisitions is to reduce the error.

Step 1-4, make the one-dimensional moving part drive the calibration block to move, take two images respectively in the moving direction, and obtain the moving direction and distance of the one-dimensional moving device. details as follows:

Make the one-dimensional moving part (4) drive the calibration block (8) to move, take two images respectively in the moving direction, and identify the calibration boards (7-1, 7-2, 7-3, 7-4 ) at the same position, obtain the moving direction and distance of the one-dimensional moving device (4).

When the one-dimensional moving part (4) drives the calibration block (8) to move, the camera (2-1, 2-2, 2-3, 2-4) correspondingly collects a calibration board (7-1, 7‐2, 7‐3, 7‐4), and identify and analyze the calibration board (7‐1, 7‐2, 7‐3, 7‐4), it can be obtained that the object to be scanned (5) The moving distance, so that the images of multiple groups of laser lines can be moved at the same moving distance to obtain the three-dimensional data on the surface of the object (5) to be scanned.

Step 1-5, turn on the laser transmitter, use the camera to collect the image formed by several non-overlapping rays in the light plane of the laser transmitter, find the line laser plane equation, and determine the line laser light plane relative to the camera coordinate system and the world coordinate system location relationship. details as follows:

Turn on the laser transmitter (1‐1, 1‐2, 1‐3, 1‐4), and use the camera (2‐1, 2‐2, 2‐3, 2‐4) to capture the laser transmitter (1‐1, 1‐2, 1‐3, 1‐4) The image formed by several non-overlapping straight lines in the light plane, find the line laser plane equation, so that the line laser light plane can be determined relative to the camera (2‐1, 2‐ 2, 2‐3, 2‐4) The positional relationship between the coordinate system and the world coordinate system.

Through two different straight lines in a plane, the equation of the plane can be determined, so that the equation of the plane is about the world coordinate system (X _W1 , Y _W1 , Z _W1 ) and the camera (2‐1, 2‐2, 2‐ 3.2-4) the position of the coordinate system, so that by laser triangulation, the surface three-dimensional data of the object to be measured (5) under the position of the laser line is obtained.

After the calibration is completed, the steps of performing three-dimensional imaging of the object to be measured (5) by full-view laser scanning are as follows.

Step 1-6, the one-dimensional moving part drives the object to be scanned to move perpendicular to the plane formed by the laser, and the camera is used to collect images of the object to be scanned at the same time to obtain the coordinate data of different surfaces of the scanned object. details as follows:

The calibration block is removed, and the object 5 to be measured is installed on the one-dimensional moving part 4 . Adjust the position of the object to be scanned (5) so that the laser line is projected on the object to be scanned (5), and use the one-dimensional moving part (4) to drive the object to be scanned (5) to be perpendicular to the laser (1‐1, 1‐2, 1 ‐3, 1‐4), use cameras (2‐1, 2‐2, 2‐3, 2‐4) to collect images of objects to be scanned (5) at the same time, and transmit the collected images back to the computer, The image is processed to obtain coordinate data of different surfaces of the scanned object (5).

Step 1-7, through the mutual conversion between the standard coordinate systems corresponding to the calibration board, the images of different surfaces formed by multiple cameras are stitched together to complete the full-view laser scanning 3D imaging. details as follows:

The coordinate data of the image obtained by line laser scanning three-dimensional imaging is the standard coordinate system under the calibration plate (7-1, 7-2, 7-3, 7-4), while multiple calibration plates (7-1, 7- 2, 7‐3, 7‐4) relative positions are known, and multiple The images of different planes formed by two cameras (2-1, 2-2, 2-3, 2-4) are stitched together to complete the full-view laser scanning three-dimensional imaging.

Stitching images of a plurality of different faces together is an important content of the present invention, and the specific implementation method is as follows:

When the one-dimensional motion device (4) drives the object to be scanned (5) to move, the cameras (2‐1, 2‐2, 2‐3, 2‐4) collect a picture every time the object to be scanned (5) moves a certain distance The image of the laser line on the surface of the object to be scanned (5), calculates the height information and stitches the multiple collected laser lines according to the moving direction and distance, to obtain the three-dimensional data on the surface of the object (5) to be scanned.

Four sets of three-dimensional data are obtained through four cameras (2‐1, 2‐2, 2‐3, 2‐4), and their coordinates are determined according to the standard coordinate system and temporary coordinate system in step 1‐2. Assume that the point coordinates of the two surfaces in the corresponding standard world coordinate system are (X _Ai , Y _Ai , Z _Ai ), and the point coordinates in the temporary world coordinate system are (X _Bi , Y _Bi , Z _Bi ).

The coordinates of the image obtained by line laser scanning three-dimensional imaging are in the world coordinate system, and the relative positions of the two calibration plates (7‐1, 7‐2, 7‐3, 7‐4) are known, and the two world coordinates can be used to The mutual conversion between the coordinate systems makes the images of different surfaces of the object to be scanned (5) formed by the two cameras (2-1, 2-2, 2-3, 2-4) overlap.

Since the world coordinate systems corresponding to these calibration boards have certain conversion relationships, the conversion relationship between the world coordinate systems corresponding to each calibration board can be expressed by an orthogonal rotation matrix R and a translation vector T. It is stipulated that the calibration plate (7‐1) is the standard world coordinate system (X _W1 , Y _W1 , Z _W1 ), and the adjacent calibration plate (7‐2) coordinate system is the temporary coordinate system (X _w2 , Y _w2 , Z _w2 ), then the transformation relationship between the two coordinates can be expressed as follows:

Among them, R is a 3×3 orthogonal rotation matrix; T is a three-dimensional translation vector, 0=(0,0,0); M is a 4×4 external parameter matrix, which represents the difference between the standard world coordinate system and the temporary world coordinate system. transformation relationship between them.

In Figure 4, according to the two calibration plates in Figure 5, we get Take the side length of the cube as d, then Transform the point coordinates in the temporary world coordinate system (X _Ai , Y _Ai , Z _Ai ) into points in the standard world coordinate system, the formula is

If the two coordinates are displayed in the same coordinate system, the two different surfaces of the object to be scanned (5) can be spliced together, which greatly simplifies the current method for identifying the edges of the two objects, and then performs image recognition through existing software. calculate.

The characteristic of its calibration is that in the calibration process, firstly, four calibration plates (7-1, 7-2, 7-3, 7-4) are respectively fixed on the four surfaces of a cube to form a calibration block (8 ). A laser, an industrial camera and a lens form a single-line laser scanning three-dimensional imaging assembly, and multiple single-line laser scanning three-dimensional imaging assemblies are placed in a ring around the object (5) to be scanned, and each assembly corresponds to a calibration block One calibration plate (7‐1, 7‐2, 7‐3, 7‐4) on (8).

When determining the coordinate system of the two worlds, let the four cameras (2‐1, 2‐2, 2‐3, 2‐4) capture a corresponding calibration board (7‐1, 7‐2, 7‐3, 7-4) image, calculate the coordinates and attitude data, make the coordinate system corresponding to the four calibration boards (7-1, 7-2, 7-3, 7-4) as the four cameras (2-1 , 2‐2, 2‐3, 2‐4) standard world coordinate system. When collecting, keep the position and posture of the calibration block (8) unchanged, and at the same time, the image of the calibration board (7-1, 7-2, 7-3, 7-4) on the other side cannot be collected.

It can be seen from the above specific embodiments that the laser triangulation method scanning 3D imaging calibration of the present invention is simple, easy to operate, and greatly simplifies the later image stitching work. The device designed in the present invention has the advantages of simple structure, low cost, convenient maintenance, great flexibility, and flexible measurement range. work scenarios and needs.

The above is only a preferred specific implementation of the present invention, but the scope of protection of the present invention is not limited to the second, and any person familiar with the technical field can easily think of it within the technical scope disclosed by the examples of the present invention. Any changes or substitutions shall fall within the protection scope of the present invention. Therefore, the protection scope of the present invention is subject to the protection scope of the claims.

Claims (8)

1. full view line laser structured light three-dimensional imaging scaling method, carries out as follows：

Step 1-1 builds full view line laser structured light three-dimensional imaging caliberating device；The full view line laser structured light three-dimensional imaging Caliberating device includes one-dimensional movement component, calibrating block, laser emitter and camera, and the calibrating block is installed on described one-dimensional Moving parts, the calibrating block is one, and at least there are three the polyhedrons in face, several faces of calibrating block circumferentially mutually to enclose for tool, marks Determine it is each on each face of block fix a scaling board, number scaling boards circumferentially mutually enclose；The quantity and calibration of laser emitter and camera The quantity of plate is corresponding, several laser emitters circumferentially the calibrating block described in face and lay；Respectively pacify on each camera A camera lens is filled, camera lens is imaged scaling board；

Step 1-2 keeps calibrating block (8) position constant, makes several cameras (2-1,2-2,2-3,2-4) while acquiring a correspondence Scaling board (7-1,7-2,7-3,7-4) image, calculate each camera (2-1,2-2,2-3,2-4) coordinate and attitude data, The standard world of the coordinate system as corresponding camera (2-1,2-2,2-3,2-4) corresponding to scaling board (7-1,7-2,7-3,7-4) Coordinate system；

Step 1-3, mobile calibrating block (8), the scaling board for keeping each camera (2-1,2-2,2-3,2-4) multi collect corresponding The sitting posture and gesture data of (7-1,7-2,7-3,7-4) pass through predetermined that method obtains often according to the nominal data of each position Position of a camera (2-1,2-2,2-3,2-4) under world coordinate system；

Step 1-4, one-dimensional movement component (4) drive calibrating block (8) mobile, take two images respectively in the movement direction, respectively It identifies each scaling board (7-1,7-2,7-3,7-4) same position in two images, acquires the movement side of motion in one dimension device (4) To and distance；

Step 1-5 opens each laser emitter (1-1,1-2,1-3,1-4), is acquired using camera (2-1,2-2,2-3,2-4) Several misaligned straight line imagings, seek line laser plane equation in laser emitter (1-1,1-2,1-3,1-4) optical plane, Determine position relationship of the line laser optical plane relative to camera (2-1,2-2,2-3,2-4) coordinate system and world coordinate system；

Step 1-6, removes calibrating block, in installation object under test 5 on the same position of one-dimensional movement component 4；Adjust scanning object Body (5) position, makes laser line projection on object to be scanned (5), and object (5) to be scanned is driven using one-dimensional movement component (4) The plane motion formed perpendicular to each laser emitter (1-1,1-2,1-3,1-4), uses camera (2-1,2-2,2-3,2- 4) image while to object to be scanned (5) is acquired, the image transmitting of acquisition is returned into computer, image is handled, is swept Retouch the coordinate data of object (5) different sides；

The coordinate data of step 1-7, the picture obtained by line laser structured light three-dimensional imaging are under scaling board (7-1,7-2,7-3,7-4) Conventional coordinates, and the relative position of multiple scaling boards (7-1,7-2,7-3,7-4) it is known that by scaling board (7-1,7-2, 7-3,7-4) mutually converting between corresponding conventional coordinates make different sides formed by multiple cameras (2-1,2-2,2-3,2-4) Picture be stitched together, complete full view line laser structured light three-dimensional imaging.

2. full view line laser structured light three-dimensional imaging scaling method as described in claim 1, it is characterized in that：The scaling board There are four pieces.

3. full view line laser structured light three-dimensional imaging scaling method as claimed in claim 2, it is characterized in that：Step 1-2, if its In a face scaling board (7-1) be standard world coordinate system (X_W1,Y_W1,Z_W1), the calibration on face one of adjacent thereto The coordinate system of plate (7-2) is temporary coordinate system (X_w2,Y_w2,Z_w2), and so on, the coordinate system of third scaling board (7-3) is interim Coordinate system (X_w3,Y_w3,Z_w3), the coordinate system of the 4th scaling board (7-4) is temporary coordinate system (X_w4,Y_w4,Z_w4)。

4. full view line laser structured light three-dimensional imaging scaling method as claimed in claim 3, it is characterized in that：Step 1-7, will be more The picture of different sides formed by a camera is stitched together, and is as follows：

When motion in one dimension device (4) drives object (5) to be scanned mobile, camera (2-1,2-2,2-3,2-4) is whenever scanning object The image of object (5) surface laser line to be scanned, computed altitude information and according to shifting are acquired when body (5) moves a certain distance Collected multi-stripe laser line is spliced in dynamic direction and distance, obtains the three-dimensional data on object to be scanned (5) surface；

Four groups of three-dimensional datas are respectively obtained by four cameras (2-1,2-2,2-3,2-4), coordinate is according to step 1-2 Plays Coordinate system and temporary coordinate system determine；Assuming that point coordinates of the two of which face in its corresponding standard world coordinate system is (X_Ai, Y_Ai,Z_Ai), the point coordinates in interim world coordinate system is (X_Bi,Y_Bi,Z_Bi)；

The coordinate of picture obtained by line laser structured light three-dimensional imaging be under world coordinate system, two scaling boards (7-1,7-2,7-3, Relative position 7-4) it is known that i.e. by mutually converting between two worlds coordinate system make two cameras (2-1,2-2,2-3, The picture of the different sides of object (5) to be scanned formed by 2-4) overlaps；

Because the corresponding world coordinate system transforming relationship of these scaling boards is certain, between the world coordinate system corresponding to each scaling board Transformational relation indicated with translation vector T with orthogonal spin matrix R；Provide that a wherein scaling board (7-1) is sat for the standard world Mark system (X_W1,Y_W1,Z_W1), scaling board adjacent thereto (7-2) coordinate system is temporary coordinate system (X_w2,Y_w2,Z_w2), then two seats Transformation relation between mark indicates as follows：

Wherein, the orthogonal spin matrix that R is 3 × 3；T is D translation vector, 0=(0,0,0)；M is 4 × 4 outer parameter matrixs, Illustrate the transformation relation between standard world coordinate system and interim world coordinate system；

In two scaling boards, obtainIt is d to take the square length of side, thenIt will be in interim world coordinate system Point coordinates isThe point being converted into standard world coordinate system, formula are

Two coordinates show that then (5) two different faces of object to be scanned just can be stitched together in the same coordinate system.

5. full view line laser structured light three-dimensional imaging scaling method as described in claim 1, it is characterized in that：Step 1-4, it is one-dimensional When moving parts (4) drives calibrating block (8) mobile, when often moving certain pulse, the corresponding acquisition of camera (2-1,2-2,2-3,2-4) The image of one scaling board (7-1,7-2,7-3,7-4) is identified analysis to scaling board (7-1,7-2,7-3,7-4), obtains The distance that object (5) to be scanned is moved every time waits sweeping to obtain the identical displacement distance of the image of multigroup laser rays Retouch the three-dimensional data on object (5) surface.

6. full view line laser structured light three-dimensional imaging scaling method as described in claim 1, it is characterized in that：The calibrating block It is a square, the scaling board has four pieces, and four pieces of scaling boards are laid along calibrating block four successively adjacent face；In contrast It answers, laser emitter, camera and camera lens respectively set four.

7. full view line laser structured light three-dimensional imaging scaling method as described in claim 1, it is characterized in that：The calibrating block It is triangular prism, the scaling board has three pieces, and three pieces of scaling boards are laid along calibrating block three successively adjacent face；It is corresponding , laser emitter, camera and camera lens respectively set three.

8. the full view line laser structured light three-dimensional imaging scaling method as described in claim 1 or 6 or 7, it is characterized in that：Described Scaling board selection standard dot scaling board.